G8TTI's Scrapbook: New Driven Element

Thursday 5 October 2017

New Driven Element

I've changed the driven element of my DK7ZB to the DG7YBN (K6STI) style. This has the advantage of a 50 ohm direct feed eleminating the need for the 50-28 Ohm DK7ZB match. I've had problems water proofing the old match and not been able to source decent 75 Ohm coax anyway.
VSWR is very low and as far as I'm able to tell there is no loss of gain. Proof of the pudding will be in the eating. EME contest this weekend so if I can make a few contacts I'll be happy if not I might have to reinstall the old DE.

The DG7YBN driven element

Update 15th October 2017

First EME contact with the new driven element

And it seems to work

Revieved this nice comment from Hartmut

On 01/11/2017 23:07, Blogger Contact Form wrote:

Nice modification on the 2 m Yagi there!
A number of low impedance Yagi are suitable of having a bent driven
element replacing mathcing devices like a T-Match or parallel coaxes.
And this also works out in the NEC model.

Well done.
73 de DG7YBN

Here's a link to Hartmut's website
DG7YBN - Low Noise Yagis

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